Testing of biological samples, whether in solid, semi-solid, or liquid form, often requires pre-treating the sample with a buffer, typically for dilution, solubilization, or extraction of an analyte in the sample to be detected. For example, biological samples, such as stool, blood, urine, saliva, or swab specimens of the cervix, urethra, nostril, or throat, as well as environmental samples, such as food product samples, soil and dust, are commonly exposed to a buffer or other solution prior to reaction with an analytic reagent and/or detection or measurement of the analyte of interest. Pre-treatment results in a sample solution that is often more suitable than the neat sample for further processing, reaction, and ultimate detection of the analyte of interest.
In a conventional apparatus, the biological sample is mixed with a buffer in a container separate from the test device used to detect the presence, or absence, of a particular analyte. In many testing protocols, a portion or aliquot of the buffer/sample solution is transferred to a second container or location for contact with a reagent to obtain a test result, e.g., a result indicating the presence or absence of an analyte of interest, and, in some tests, its quantity if the analyte is present.
Such conventional prepackaged test devices and kits are prone to user error, particularly by non-laboratory personnel. Untrained users can have difficulty with the multiple steps involved, particularly the requirement of pre-treating the biological sample with a buffer and then transferring an aliquot to a second container. Another disadvantage of conventional test devices is that many do not readily accept solid or semi-solid samples, which require pre-mixing with a buffer prior to reacting with a reagent to obtain a test result.
The need exists in the art for an apparatus in which the steps involved for collection and detection of an analyte in a biological sample can be performed in a single apparatus that is reliable and accurate irrespective of the skill level or training of the user. Moreover, there is a need for an apparatus that minimizes the need for user manipulation of, and contact with, sample by, for example avoiding the need for transfer of a sample aliquot to a separate apparatus for detection of an analyte. An apparatus that provides for sample collection, mixing of the sample with a buffer, reaction of the buffer/sample with an analytical reagent and detection and/or measurement of an analyte in a biological sample is desired.